Technical Field
The present invention relates to the field of electronic horns for motor vehicles and boats, and in particular, to an intelligent electronic horn and an implementation method thereof.
Related Art
As electronic horns have rapidly gained popularity, increasingly higher requirements are imposed on the service life and operating stability of horns. Besides the waterproof performance of the horn and diaphragm breakage, other factors affecting the normal operation of the horn mainly include the follow three aspects: the effect of the change in power supply on the sound level and service life of the horn; the effect of the change in temperature on the sound level and sound quality of the horn; and the effect of the change in air pressure on the sound level of the horn. Although a variety of improvement methods have been proposed in recent years, neither of these methods provides a complete solution for all the three failure modes of the electronic horn.
The frequency of a conventional electronic horn usually cannot be changed after delivery and commissioning. Due to the effect of ambient temperature or air pressure on the spiral sound channel of the electronic horn, there is a relatively large change in the resonance frequency of the spiral resonant cavity of the horn, leading to a relatively large attenuation of the sound pressure level of the horn. Therefore, for many horns, when used in high temperature environments, the resonance frequency of the horn drifts to a lower frequency due to the effect of the change in temperature on the air density and the volume of the resonant cavity. For many horns, when used in low temperature environments, the resonance frequency of the horn drifts to a higher frequency due to the effect of the change in temperature on the air density and the volume of the resonant cavity. If the atmospheric pressure decreases as the altitude increases, the fundamental frequencies of the spiral resonant cavity of the electronic horn and a drive circuit also greatly deviate, causing that the sound pressure level of the horn is significantly attenuated, and the horn can no longer operate normally.
Generally, the driving power of electric horns for motor vehicles and boats, either of mechanical or electronic type, varies greatly due to the power supply voltage. For example, electric horns are required to operate at a voltage of 9-16 V, and the power of a horn with a rated voltage of 13 V and a rated operating current of 4 A changes significantly in the range of 25 W to 79 W. This has great impacts on the service life and sound effect of the horn, and easily leads to a significant attenuation of the sound level at a low voltage and leads to noise caused by collision (also called striking) between movable and fixed cores of an electromagnet that drives the diaphragm of the horn to sound at a high voltage. This phenomenon not only deteriorates the sound quality but also greatly shortens the service life of the horn. Although there are approaches of reducing the current by means of constant current source driving or by using an analog device to reduce the drive pulse width, the driving power cannot be accurately controlled, and occurrence of such failure modes cannot be eliminated.